I am pleasantly surprised by this quest. I just got back into Avatar due to childhood nostalgia. In regard to the main character, Zhang-Li is like a weird fusion of Toph and Azula, although not quite. Zhang-li is very arrogant, but it is an arrogance rooted in her genius level intelligence and high-level abilities as well as her status as the Earth Kingdom's heir apparent and Princess. She comes off as unkind and uncaring for others, but this is the result of her closed and royal upbringing, rather than any sort of innate cruelty. She does have it in her to care about the well-being of others and of her subjects. But right now, her goals are more self-centered in that she wants to defeat the Fire Nation to restore the Earth Kingdom and prove her greatness, rather than out of any concerns for the common people.
Other than that, it would be interesting to see Princess Zhang-li advanced the Earth Kingdom to proper war-footing. As we all know, a properly modernized and militarized Earth Kingdom is more than capable of driving the Fire Nation from its borders. It is just that the Earth Kingdom is badly divided and unable to fully used its considerable potential strength against the Fire Nation. If Zhang-li is able to place just place just a fraction of the Earth Kingdom onto proper war mobilization, she would be a very difficult opponent for the Fire Nation. At the very least, Zhang-li should be able to stalemate the Fire Nation just beyond the walls of Ba Sing Se.